# OPL AUv3 FM Synth — OPL chip based synth

> Yamaha OPL2 chip emulator for music production and retro game soundtracks. (iPhone/iPad app by DiscoDSP LLC.)

- Source: https://appshunter.io/ios/app/opl-auv3-fm-synth/id1516617949 (this page in markdown: same URL + `.md`)
- Developer: [DiscoDSP LLC](https://appshunter.io/developer/1465262828)
- Category: Music
- Price: $9.99
- Rating: 4.30/5 from 23 App Store ratings · 10 written reviews indexed
- Age rating: 4+
- Requires: iOS 15.0 · 35 MB
- Released: 2020-06-04
- Data updated: 2026-08-25
- Monetization: paid
- User reviews in markdown: https://appshunter.io/ios/app/opl-auv3-fm-synth/id1516617949/reviews.md

## What is OPL AUv3 FM Synth?

The Yamaha OPL chips, introduced in 1985, shaped the sound of 80s and 90s video game soundtracks. discoDSP OPL emulates their FM and additive synthesis, including the distinctive percussion mode. With up to 16x oversampling for crystal-clear sound and over 2000 included presets, discoDSP OPL is ideal for classic game soundtracks, electronic music, or crafting unique sounds.

Play it with the built-in on-screen keyboard on iPad, a MIDI controller, or your DAW. On iPhone, connect a MIDI keyboard or run it as a plugin.

CORE FEATURES

• YMF262 (OPL3) FM engine with all eight waveforms per operator.
• Percussion mode with bass drum, snare, tom, cymbal, and hi-hat.
• Over 2000 SBI instruments, organised by category.
• Two operators with wave, multiplier, envelope, and attenuation.
• Selectable oversampling from 1x to 16x, with a separate bounce setting.
• Key-tracking stereo panning that places notes across the field by pitch.
• On-screen keyboard with pitch and modulation wheels (iPad, standalone).
• Analog modeled wave shaper on the carrier.
• SBI instrument import and export through the Files app.
• Bluetooth MIDI device discovery.
• AUv3 plugin for GarageBand, AUM, Cubasis, BeatMaker, and Drambo.

THE OPL SOUND

Two-operator FM is the sound of Adlib and Sound Blaster era games. Each voice pairs a modulator and a carrier, each with its own waveform, frequency multiplier, envelope, and attenuation. Route them in FM for the metallic, bell-like timbres the chip is known for, or in additive to stack the two operators as independent tones.

Feedback on the modulator pushes the tone from clean to gritty, and all eight OPL3 waveforms are available on every operator: sine, half sine, absolute sine, quarter sine, alternating sine, camel sine, square, and logarithmic sawtooth. They are the chip's own, not approximations.

PERCUSSION MODE

The rhythm section repurposes the last channels into five dedicated drum voices: bass drum, snare, tom, cymbal, and hi-hat. It is how the chip made drums without samples, and it is included here in full.

INSTRUMENTS

Over 2000 SBI instruments are included, sorted into categories: bass, drum, FX, guitar, keys, and more. Load one from the menu, step through them with the previous and next buttons, or import your own SBI files from the Files app. Anything you edit can be exported back out as SBI.

OVERSAMPLING

The chip is emulated at up to 16 times the host sample rate, which stops the FM sidebands folding back into the audio band as aliasing. Playback and offline bounces have separate settings, so you can run a lighter factor while playing and render at the highest quality.

ON-SCREEN KEYBOARD

The standalone app on iPad includes a keyboard with pitch and modulation wheels, so you can play without any external hardware. The mod wheel drives a vibrato LFO with continuous depth, going well beyond the original chip's fixed two-position vibrato. Hide the keyboard from the settings menu when you would rather give the panel the whole screen.

STANDALONE OR AUV3

Load OPL inside GarageBand, AUM, Cubasis, BeatMaker, Drambo, or any AUv3 host, with settings saved in your project. Or run it standalone with a MIDI controller, over Bluetooth MIDI, or with the on-screen keyboard.

## Key features

- OPL2 chip emulation
- FM and additive synthesis
- Distinctive percussion mode
- 16x oversampling
- Over 2000 presets
- Standalone MIDI keyboard support

## Recent user reviews (10 of 10)

All indexed reviews: https://appshunter.io/ios/app/opl-auv3-fm-synth/id1516617949/reviews.md

### 1/5 — This app sucks.

*2026-03-10*

It just does.

### 1/5 — Please add a keyboard… and version 2.7 breaks AU compatibility

*2025-08-13*

First, version 2.7 update no longer works as an Audio Unit in GarageBand. Second, if you could add an onscreen keyboard it would make the app more useful as a standalone and speed up new patch creation. Thank you.

### 5/5 — Incredible!

*2022-01-30*

If you’re a FM nerd like me and were around when the first fm game music came about, you will absolutely love this. Very authentic, lovely lo-fi FM sound with endless presets and many sounds that will melt you with nostalgia. Superb!

### 4/5 — Surprisingly cool sound possibilities

*2021-08-30*

More inventive than it looks, a very nice source of unexpected sounds.

### 4/5 — Sounds truly excellent but UI has some limitations, depending on your need.

*2021-03-30*

For people who just want to load a patch from the tremendously large built-in library and integrate with a host for sequencing from another app (or playing via midi keyboard) this app would be great. Not so much for my purposes however, though I can’t fault it a great deal for this. It’s a fantastic emulation and the patches are solid and plentiful. Below I will explain why it didn’t work for me though, in case you are planning similarly:

Since this is an accurate emulation of a real hardware chip using a standardized OPL fm preset format, I was counting on there being an easy method for programming, testing and storing presets within the app. My goal in buying this was to have a portable way to create and build a library of my own original patches to use with Adlib Tracker ][. This use-case has proved mostly fruitless however for the following reasons—

1. The standalone app does not properly fit an iPhone screen (iPhone X at least); the bottom row of buttons runs below the edge of the screen.
2. There is no way to save your own patches directly inside the app, only load the existing presets.
3. There is no built-in keyboard, basically it’s  a plugin more than an app and relies on a host to do most useful things. 
4. On an iPad 11” I wasn’t able to scale the view to fit both the complete instrument UI and the AUM virtual keyboard on-screen simultaneously, making it cumbersome to edit, play and test custom patches.  (Honestly this one might be user error, please correct if I’m wrong and there’s a way to achieve this)

### 4/5 — Great except for UI

*2020-12-13*

This is a great, straightforward 2-op FM synth, but on my 5th gen IPad mini, the UI of the AUv3 in Cubasis and AUM is tiny. It doesn’t even come close to filling up the AU window the way other instruments do. It would be nice if the dev would rework the interface for smaller IOS devices rather than simply porting the interface from the desktop version. Otherwise, I’m glad to have it on my iPad. It’s a classic!

### 5/5 — This is what I was looking for!

*2020-09-25*

I’ve been trying to find this “sound” on iOS for a few years.
There are a lot of 8-bit/chip/lo fi apps but I never felt the sound was quite right; they didn’t sound like it did back in the day when I was kid.
I have come to love OBx and in similar fashion this synth sounds just as genuine and authentic as the original synth it emulates. 
This devs apps deliver true, authentic sounds with plenty of parameters to manipulate. 
I don’t know much about the technical side of it, but if you want the best 80s synth tones, you found it.

### 5/5 — Better preset visibility please!

*2020-06-24*

Great work but would love a more visible preset bar. Sounds great, thank you!

EDIT: Preset bar has been updated and it’s perfect.

**Developer response:** Thanks for the feedback. This has been addressed in 1.7 release.

### 3/5 — Decent easy fm synth

*2020-06-07*

Good sounding simple to use fm synth. However, it needs full automation support / midi cc and finer resolution for the parameters

### 4/5 — Please include file name display

*2020-06-06*

These sounds are really great, and the ammount of presets is over the top.  But because there are so many presets, it would be great to be able to recall favorites.  However when changing programs up and down (+, -) there is no display telling you what preset you’re playing, and therefor no easy way to recall it later.  The current preset is also not highlighted in the preset menu when browsing.  This would add invaluable functionality to a very cool-sounding synth.

**Developer response:** Current preset highlight and preset name display is featured in 1.7 release.

## Frequently asked questions about OPL AUv3 FM Synth

### What is OPL AUv3 FM Synth?

OPL AUv3 FM Synth is a music application that emulates the Yamaha OPL2 chip, known for its use in 80s and 90s video game soundtracks. It allows users to create classic game sounds and electronic music.

### Does OPL AUv3 FM Synth require any additional hardware?

Yes, the standalone version of OPL AUv3 FM Synth requires a MIDI keyboard to be used. This allows for direct control and performance of the synthesized sounds.

### How many presets are included with OPL AUv3 FM Synth?

OPL AUv3 FM Synth comes with over 2000 included presets. These presets provide a wide range of sounds for users to explore and utilize in their music productions.

### What is the price of OPL AUv3 FM Synth?

OPL AUv3 FM Synth is a paid application priced at $9.99. This one-time purchase grants access to all its features and sound capabilities.

### How often is OPL AUv3 FM Synth updated?

The latest version, 2.7.2, was released on March 6, 2026. While specific update frequency isn't detailed, the app has seen consistent development since its release in 2020.

### What devices is OPL AUv3 FM Synth compatible with?

OPL AUv3 FM Synth is compatible with iPhone, iPad, and iPod devices. It is designed to run on Apple's mobile operating systems.

### What is the age rating for OPL AUv3 FM Synth?

OPL AUv3 FM Synth has an age rating of 4+. This indicates it is suitable for users of all ages, with no mature content.

### Does OPL AUv3 FM Synth have ads?

No, OPL AUv3 FM Synth does not contain advertisements. As a paid application, it offers an uninterrupted user experience without any ads.

## Version history (last 5 releases)

### 3.0.1 — 2026-08-08

Fixed instruments missing on new installs. The factory sound banks are now copied into the shared folder on first run, so the app and the AUv3 plugin both see them.

### 3.0 — 2026-08-06

PL has been rewritten from the ground up.

NEW FM ENGINE
The synthesis core is now built on the YMF262 (OPL3), replacing the previous OPL2 emulation. All eight OPL3 waveforms are available on every operator, where before there were four. The synthesis core, register layer, parameter handling, and interface have all been rewritten.

SOUND QUALITY
Oversampling up to 16x is now applied to the chip itself, cutting the aliasing FM produces at high modulation settings. Pitch, envelope timing, and key scaling stay constant across every oversampling setting. Playback and bounce have separate settings, and offline renders use a linear-phase filter and report their latency, so a bounce matches what you monitored.

NEW INTERFACE
Redrawn as resolution-independent vector graphics in place of the fixed-size bitmaps, and freely resizable with a zoom menu. Voice activity is now shown live on the envelope displays.

NEW PARAMETER
Panning: a key-tracking stereo spread that places notes across the field by pitch.

ON-SCREEN KEYBOARD
The iPad standalone app now has a MIDI keyboard, so OPL no longer needs an external controller to play. It sits below the panel with pitch and modulation wheels and octave buttons at each end. The modulation wheel drives a vibrato LFO with continuous depth, going well beyond the chip's own fixed two-position vibrato. Toggle it from Menu > Show MIDI Keyboard.

ON iOS
Oversampling settings are now available, with playback and bounce quality each set from 1x to 16x and remembered between sessions. Loading and exporting SBI instruments through the Files app and iCloud Drive has been fixed, and the AUv3 no longer opens at the wrong size in hosts.

COMPATIBILITY
Existing projects and presets load unchanged, with automation assignments preserved. Adds a new Init Bass factory program.

FM synthesis now uses ymfm by Aaron Giles under the BSD 3-Clause License.

### 2.7.2 — 2026-03-06

Added App Data Group shared container between Standalone and AUv3 builds.
Added Bluetooth MIDI device discovery dialog to settings menu.
Added iTunes File Sharing support for SBI instruments.
Added Carrier analog modeled wave shaper parameter.
Fixed Carrier Multiplier label alignment.

### 2.7 — 2025-08-13

Oversampling switched to 8x for better CPU performance and similar sound quality.
New menu button adds Export button with Load/Export options.
Modern popup menus with improved styling.
Per-project window size memory.
Reduced CPU usage during parameter automation and GUI processing.
Smart processing only affects active channels.
Optimized voice management eliminates audio dropouts.
Enhanced oversampling initialization and memory management.
Improved plugin state management and build system updates.
Major framework update.

### 2.4 — 2024-08-14

16x oversampling for pristine, alias-free sound.  
Optimized voice management for enhanced efficiency and performance.  
Updated interface with modern elements for a smoother user experience.  
Significant core framework improvements for greater stability and performance.  
Fixed crash issue when triggering more than 9 voices simultaneously.

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## More apps by DiscoDSP LLC

- [OB-Xd AUv3 Synth](https://appshunter.io/ios/app/ob-xd-auv3-synth/id1465262829)
- [Scope AUv3 Visualizer](https://appshunter.io/ios/app/scope-auv3-visualizer/id1512571419)
- [Schroeder AUv3 Reverb](https://appshunter.io/ios/app/schroeder-auv3-reverb/id1527402838)
- [ThrillMe AUv3 Compressor](https://appshunter.io/ios/app/thrillme-auv3-compressor/id6633713618)
- [OB-Xd 3 AUv3 Synth](https://appshunter.io/ios/app/ob-xd-3-auv3-synth/id6654915211)

All apps by DiscoDSP LLC: https://appshunter.io/developer/1465262828

## Related topics

[opl auv3 fm synth](https://appshunter.io/ios/topics/opl-auv3-fm-synth) · [ivcs3](https://appshunter.io/ios/topics/ivcs3) · [ruismaker fm](https://appshunter.io/ios/topics/ruismaker-fm)

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-25.*